import random
from numpy import *
import matplotlib
import matplotlib.pyplot as plt
x = random.rand(50, 30)
# basic
f1 = plt.figure(1)
plt.subplot(211)
plt.scatter(x[:, 1], x[:, 0])

# with label
plt.subplot(212)
label = list(ones(20)) + list(2 * ones(15)) + list(3 * ones(15))
label = array(label)
plt.scatter(x[:, 1], x[:, 0], 15.0 * label, 15.0 * label)

# with legend
f2 = plt.figure(2)
idx_1 = find(label == 1)
p1 = plt.scatter(x[idx_1, 1], x[idx_1, 0], marker='x', color='m', label='1', s=30)
idx_2 = find(label == 2)
p2 = plt.scatter(x[idx_2, 1], x[idx_2, 0], marker='+', color='c', label='2', s=50)
idx_3 = find(label == 3)
p3 = plt.scatter(x[idx_3, 1], x[idx_3, 0], marker='o', color='r', label='3', s=15)
plt.legend(loc='upper right')